1. Technical Field
The present invention relates generally to an evolved gas analyzer and a method for analyzing evolved gas, the method analyzing gas components evolved by heating a sample, thereby identifying, quantifying, etc. the sample.
2. Description of the Related Art
In order to increase flexibility of resins, plasticizers such as phtalates, etc. are added to the resins. After 2019, four substances of the phtalates will be restricted under the restriction of hazardous substances directive (RoHS). Therefore, it is required to identify and quantify the phtalates in the resins.
The phtalates are volatile substances such that a conventional evolved gas analysis (EGA) is applied to analyze the phtalates. The EGA is a method used to analyze gas components evolved by heating a sample by using a gas chromatograph or using various analyzers applying mass spectrometry, etc.
In addition, in the evolved gas analysis, the evolved gas component flows with carrier gas such as nitrogen gas, etc. so as to be introduced into a detecting means. However, when a plurality of gas components are evolved, gas density is too high. Therefore, the gas density exceeds a detection range of a detecting means and thus, a detection signal is overly scaled, whereby the measurement is inaccurate.
Therefore, technology of increasing flow rate of the carrier gas that is mixed with the gas component to dilute the gas component so as to reduce the gas density, when the detection signal of the detecting means exceeds the detection range are disclosed in Patent Documents 1 and 2.